Many medical procedures today require the need to reconnect internal vessels after a portion has been removed. For example, in various procedures such as where a section of colon has been excised, it is necessary to rejoin the remaining portions of the colon through an end-to-end anastomosis (e.g., connection of healthy sections of the colon or rectum after a cancerous or otherwise diseased portion has been surgically removed). Many medical devices are available to perform the reconnection of the two portions of the colon using a device to apply a double row of staples, for example. Other existing known devices to perform an anastomosis on the colon, for example, require a surgeon to dissect the diseased portion of the colon, secure the separable ends of an anastomosis device into the healthy portions of the colon with purse string sutures, bring the device ends together, and perform the anastomosis.
As mentioned, to use some of the devices above, each portion of the colon or other vessel to be reconnected is usually provided with a purse-string suture. Purse string sutures are continuous, circular inverting sutures, used to close a tubular section of tissue, e.g., intestinal tissue, prior to the performance of the end-to-end anastomosis with a suturing instrument. As such, a purse string suture is a single thread stitched to surround an opening of the tubular section and then is pulled tight (like a purse-string) to close the hole.
Typically, a purse string suture is attached to a surgical needle that is used by a surgeon to manually stitch the purse string suture about the periphery of the tubular section of tissue. A purse string suture is a suture loosely placed around cut end of a vessel (e.g., any end of an intestinal organ) in a manner to act as a purse string so that after the purse string suture is stitched to the tissue, the ends of the purse string suture can be pulled to tighten the stitches and draw the tissue together (e.g., like closing a purse). Then, the purse string suture is wrapped and tightened about the tubular section of tissue. In the manual stitching of the purse string suture, it can be difficult to obtain uniform penetration of the purse string suture into the tissue. It also can be difficult to obtain stitches that are uniform in length and are evenly spaced apart. As a result, some of the stitches may rip away from the tissue when the ends of the purse string suture are pulled. Further, at times, it may be difficult for the surgeon to reach an area within the human body cavity to place the purse-string suture.
Another drawback of applying purse string sutures manually is that a surgical opening large enough to fit the surgeon's hands may be required. With the progression toward less invasive surgical techniques, e.g., laparoscopic surgery, that permit visualization and manipulation of surgical instruments through less invasive openings in the human body, a compact surgical instrument is desired that automatically places purse string sutures in tissue structures and obviates the need for space to view the stitching procedure and accommodate the surgeon's hands.
Accordingly, a surgeon may alternatively use a purse string device to apply the suture. Purse string suture devices are known that comprise a pair of serrated tissue clamping jaws provided with teeth for clamping the tissue to be sutured therebetween. Such devices include needle passages which extend through the teeth on each jaw for receiving a needle attached to a suture to be threaded through the tissue. In use, the tissue to be sutured is clamped between the jaws and the needle is manually passed through the needle passages in both jaws to thread the suture through the tissue. Thereafter, the jaws are opened and the purse string suture is tightened and wrapped to draw the tissue together. Many variations of this device that use a clamping mechanism are known, so as to clamp the end of a vessel tube and apply the suture to close the opening.
In use it is desired that a sufficient amount of tissue be clamped and pinched into the spaces between the clamping jaws to receive the needles and suture threads that are driven through the passages in the jaws. However, due to configurations of the jaws and spaces therebetween, at times only a limited amount of tissue may be pinched into the path of the needles. Thus, it is possible that an insufficient amount of tissue may be gathered into the spaces between the teeth to properly perform the purse string suturing technique.
Another obstacle is the size of the device. It is not always possible to use such devices in the desired place within the human body cavity due to size of the device and lack of maneuverability of the surgeon within the cavity. For example, it is not always desirable to create an opening in the human body large enough to place the clamp-like purse string suture device in position to apply the suture. As such, depending on the location of the vessel, size of the vessel, etc., it is often difficult, if not virtually impossible, to place a suitable purse string suture in a manner so as to insure a desirable reconnection of the vessel. This is true, for example, in low colon anastomosis where it may be difficult to place the purse string suture on a distal end of the vessel especially using less invasive laparoscopic purse-string suturing techniques.